Incandescent lamp.



M. M. MERRITT. INCANDESOENT LAMP.

APPLICATION FILED FEB. 24, 1906.

Patented Aug". 6, 1912.

INVENTUH; ham, m-W

aucannnscam ,LAMP.

Specification of Letters Patent. Application filed February 24, 190

Serial No. 3025731 To all whom it may concern: I

Be it known that I, MA'rrHnw M. MER- me, a citizen of "the UnitedStates,residing county of Essex, and State of at Middleton, Massachusetts, haveinvented an Improvement in Incandescent Lamps, of which the followingdescription,

' incandescent lamps, having more in connection with the accompanyingdrawings, is a specification, like letters on the drawings representinglike parts.

My invention relates to improvements in particularly for its object theprovision of a lamp so constructed as to prevent, or render com--'mere1ally impracticable, its .other words,

renewal, or,,in the substitution, or attempted substitution, of a-ne wfilament for. the old one when the latter is burned out or otherwiserendered useless or ineflicien't. It is a common practice to purchase ata relatively slightcost high grade lamps thus burned cut, open the endor tip of the lamp and replace the old filament with a fresh one. llhenew filament having been attached to the leading-in wires, the lamp isexhausted by the usual process, the bulb sealed up, and

the renewed or convertedlamp in condition 1 tice, preventing frequentlyconducted by irresponsible again for use. This renewing process ispersons lacking the necessary skill and knowledge in the art andemploying inferior materials, so that its product, in any event aninferior one, is very often a low grade lamp, though having everyappearance of a high grade one. My invention aims to correct thispracpossible injury to the reputation of the maker of the original lampand deception of t-he public as well. v Y

My invention will best understood by reference to the followingdescription when taken in connection with the accompanying illustrationof'one or more specific embodiments thereof, while its scope will bemore particularly pointed out in the appended claims.

Referring to the shows a lamp embodying one form of my invention,and'Figs. 2 and 3 show modifications thereof.

In the described embodiment of my invention I take advantage of theconditions under which certain parts of the renewal process are carriedout and provide for the development of certain-manifestations when soconstruct the lamp,

heat which can be interiorly drawings,Figure 1 This occurs during thoseconditions are present which preferably result in injury of some kind tothe lamp. I

While other means than those described may be employed and otherconditions relied upon to cause the desired manifestathe renewalprocess, in the embodiment of my invention here selected forillustration I withsuch means, that,when subjected to a violent orabnormally high degree of heat,

,the bulb, stein-.01 other essentiahpart of the lamp is in ured. In thecase ofthe bulb or the stem the injury may consist of a punc ture,-dueto fracture or other collapse, so as to render it-impossible thereafterto maintain a commercial vacuum within the bulb space. This action canreadily be effected,

for during the-process: of renewal the lamp 1S repeatedly subjected toviolent heating. For example one of the characteristics of an old orburned-out 'lamp, and invariably where it has been used any length oftime, is a darkening or clouding of the is caused by a deposit of finelydivided matter thrown'ofi' by the filament or joints duringincandesccncc. This deposit is a considerable factor alone in reducing,the effective candle power of a'lamp and its removal constitutes one ofthe usual and first steps in the renewing process after the opening ofthe bulb tip. This is ordinarily accomplished by subjecting the lamp,while the latter is slowly revolved, to some intense heat, such as theheat of an alcohol or hydrogen vapor torch. The heat which is usuallyimparted to the lamp and necessary to volatilize and drive ofi the soliddeposit is probably not less than-500 or 600 Fah., and, of course,abnormally in excess of any heat to which the lamp bulbis ever subjectedduringits customary and intended usev and greatly in excess of themaximum imparted to the bulb by the incandescent filament For example,the heating of the bulb of an ordinary sixteen candle power lampc'anscarcely exceed 150 Fah. even when the filament is carrying themaximum current of which it is capable. Again, the tip of the lamp issubjected to excessive heat subsequent to the urning. out of the depositdescribed. the welding on tothe Patented Aug. 6, 1912;

t ions. as well as'other results relied upon to cause in ury to the lampor obstruction to i or provide the same bulb, which perforated bulb tipof the short glass stem or tubulature through which the subsequentexhaustion of the lamp-is effected. This involves the heating of thebulb tip in a blow pipe flame causing, through conduction and radiation,the heating ofthe other parts of the lamp as well. 1 Referring-to theembodiment of my in vention shown in Fig. 1 there is shown a lamp ofordinary construction but'provided with means responsive to a highdegree of heat for causing injury to; the bulb. The

, lamp there shown is provided with the usual glass bulb a, cemented orotherwise secured in the usual fashion to and within the metal socket band having the usual form of glass stem 0, through which pass theleading-in wires d having the sealed-in platinum ends e, the latterconnected to the filament 7. During original manufacture of thelamp .insome suitable part thereof, preferably within.t-he lamp space, as forexample upon the tip of the stem there is placed a deposit, representedat g, of. some material or substance which is preferably unafiected bythe ordinary temperatures to which the lamp is subjected, but, whensubjected to such violent heating as accompanies the burning out of thebulb deposit, is caused to injure I the bulb or other'la'mp parts. Forexample,

such substance may, consist of a suitable quantity of sulfur nringledwith graphite paste or other appropriate binder and appliedthrough the aid thereof to the stem tip. Sulfur, when highlyhe'ated,produces a deposit which will smear the inner walls of the lamp andrenderthe saine unsalable.

If removable at. all, such deposit can only be removed by such steps as'will increase 0 the expense of the renewal process to a pro hibitivedegree-.-

To protect the chemical deposit against possible attempts to remove thesame by ma: nipulation carried on through the opened end of the bulbthere may be ;provided means, such for example, as the shield k,

which herein consists of a thin disk of por celain or other suitablematerial, secured to the anchor wire sup ort i just above the tip of thestem. The s eeve is-slit to embrace the filament joints and perforatedto he slipped secured in any suitable way, as by the glass head 1'.

location as well, ma'y be varied as desired, and in-Fig.'2- I have showna. lamp,

-. where the insertedichemical, whichis represented at g, is spread uponthe inner walls to of the bulb, wherethe man joinedtothe' In thisposition the sulfur base of thestem,

used when heated will or other, sub tance employed are unexample, awaterproof filler for lamp is violently heated? over the anchor W11e tOwhich it is Not only thenature of the substance,- butafl'ected by theheat tit which the lamp is ordinarily subjected when" in use.

My invention is not limited --to the 11370 duction of any particularinjury to the lamp or to the injury to any'particular parts For example,in F ig. 3,1 have shown a sub stance, represented at g, placedinteriorly within the hollow part of the stem whep the lamp was'originally constructed. Such substance is preferably of a volatilenature such that when the lamp is violently heated to a degree safelybeyond the-maximum heating limit due to ordinary lamp use, an excessivevolume of gaswill he suddenly p oduced.-

Such substance, for example, may consist of 89 a number of grains of gunpowder, which, when subjected to the heatof the. burning out process,,will explode, producing sulficient pressure within the stem to ruptureor puncture. the walls thereof and render the '3 lamp useless Withoutreplacing some of its essential parts, which result is a prevention j ofits commercial renewal.

'Where the explosive or volatile substance is placedin the-Shem; itseffect may be made disastrous to the lamp without danger to theoperator, for thexamount' of chemical may be so proportioned astofracture the walls of the stem without injuring the outer walls of thebulb. The chemical or other substance inserted in the stem may beprotected against exterior tamperingsave by removal of the socket itselfthrough theapplicationof suitable guarding-means, as for h 09 end of thestem." w j The insertion of the chemical or other-. substance within thestem permits its application to the lamp after the process of lamp vconstruction has been substantially completed. This may be done,afterthe process of exhaustion and after the lamp has been attached toits socket and just before the small perforation in the bottom of thesocket v, has been'closed'. ,4

, Claim- J ,c I g a 1. A non-renewable incandescent lamp havingaj-filament, abulhand means for'defacing the walls of thelamp space whenthe '2. A" none-renewable incandescent vlamp having a filament, a bulband means for defacing the walls of the bulb on attempted renewal of thelamp.

3. A non-renewable incandescent lamp having a fil'amenha bulbandmeansfor de- Y facing the .inclosing walls of the lamp space onattempted'renewal of the lamp.

4. An incandescent 'lampoha'vmg a fila;

me nt', a bulb and means within the vacuum space of the lamp forinjuring the inclosing wallsof the lamp space when'the lamp is violentlyheated.

5. A non-renewable lamphaving a filament, a bulb and a substance placedwithin 1 circuit of the lamp,

the vacuum space of the lampat the time of its original construction andindependent of the electric circ i't thereof and adapted thereto.

6. A non-renewable incandescent lamp having a filament, a bulb'and meanswithin the vacuum spaceof the lamp for injuring the lamp on attemptedrenewal thereof.

7. non-renewable incandescent lamp having a filament, a bulb andfracturing means within the vacuum space of the lamp for injuring thelamp on attempted renewal thereof.

8. An incandescent lamp having a filament, a bulb and a substance placedwithin the lamp atthe time of its original constructionand independentof the electric circuit 20 thereof and adapted to work injury to thelamp on the attempted renewal thereof.

9. A non-renewable incandescent lamp having a deposit in a suitablerecess thereof of a substance independent of the electric adapted toinjure the lamp on the application of a high degree of heat, and meansfor preventing access to said substance.

10. A non-renewable incandescent lamp having means for injuring thewalls of the filament space on the attempted renewal of the lamp, saidmeans comprising an expansion member having a different coefiicient ofexpansion from that of glass, said member being located to contact withthe glass walls of the filament space, and adapted thereby to fracturethe same on abnormal heating of the lamp.

11. A having thereof, said means comprising an expannon-renewableincandescent lamp means forpreventing the renewal sion member forcausing injury to the lamp on violent heating thereof through theexpanion of said member.

12. A non-renewable incandescent lamp having a filament, a bulb, andmeans within the lamp for fracturing the inclosing walls thereof onattempted renewal of the lamp.

13. A non-renewable incandescent lamp having interior-stem-fracturingmeans for preventing the renewal of the lamp.

14. A non-renewable incandescent lamp having means for injuring the stemthereof on the attempted renewal of the lamp.

15. An incandescent lamp having a filament, a bulb, and means, withinthe lamp to rupture the walls thereof on the attempted renewal of thelamp.

16. A non-renewable incandescent lamp having a filament, abulb, andmeans within the stem to rupture the walls thereof on the application ofan abnormally high degree of heat.

17. An incandescent lamp having a filament, a bulb, and means within thelamp for injuring the inclosing walls of the filament space when thelamp is violently heated.

'18. A non-renewable incandescent lamp having means to fracture the stemon the attempted renewal of the lamp. I

19. A non-renewable incandescent lamp having a filament, a bulb, andexpanding means to fracture the lamp walls inwardly on attempted renewalof the lamp.

In testimony whereof, I have signed my name to this specification, inthe presence of two subscribing witnesses.

MATTHEW M. MERRITT.

Witnesses NINA'B. SHIRLEY, THOMAS B. Boom.

- Copies of this patent may be obtained for live cents each, byaddressing the "Commissioner of Patents, l v Washington, D. G.

